HDR video

* Toggles a parameter (string videoHdrParam in config.xml) on/off.

Change-Id: Iafedf74b7191ce35ab982c52f3188dc566de9d7b
camera: reset camera surface on previewstart()

fixes aspect ratio on camera switch bug

JIRA: CYAN-1085

Change-Id: Ic91e0454588a987e72e5336ab9d01bdd249f13e6